Camshaft adjusters, in particular hydraulic camshaft adjusters, are already known from the prior art from U.S. Pat. No. 6,276,321 B1, for example.
Such devices for variable adjustment of the control times of gas exchange valves are used in modern internal combustion engines to be able to variably set the phase ratio between the crankshaft and the camshaft in a defined angle range between a maximum “advance” position and a maximum “retard” position. For this purpose, the camshaft adjuster is integrated into a drive train, via which the torque is transferred from the crankshaft to the camshaft. This drive train may include a traction means such as a belt drive or a chain drive. A gear drive may also be used in this regard.
Details of how camshafts are modified in comparison with a crankshaft of an internal combustion engine are to be found in the publications DE 10 2010 012 482 A1 and DE 2011 003 556 A1, for example. A device for controlling and/or influencing valve control times of an internal combustion engine is also known from DE 10 2010 024 596 A1 and DE 10 2009 037 976 A1.
The details described in these publications also form the basis for the refinement presented here and will not be discussed further here but should be considered as integrated therein.
Previously, the cavity between the rotor and the stator, which is to be filled with a hydraulic fluid, such as a liquid, namely oil, has been sealed by at least one cover with respect to the outside. A screw connection is usually used here.
However, such a screw connection approach has the disadvantage that it requires many individual parts. This makes the assembly difficult. Furthermore, the possibility of leakage cannot always be ruled out reliably. Furthermore, such a screw connection approach is relatively heavy, so that heavy camshaft adjusters must be used. This is disadvantageous for the consumption of the motor vehicles, which use such camshaft adjusters on internal combustion engines. The precision of the adjustment angle between the rotor and the stator is also not adequately high in some application cases. Unfortunately, ease of dismantling and/or misuse cannot be ruled out in all application cases.